1. Field of the Invention
The present invention relates to a photoelectric converting device for converting an output current of a photoelectric converter such as photo diode into a voltage.
2. Description of the Prior Art
A photoelectric converting device is used, for example, in a photo detector of an optical pickup apparatus installed in a compact disk player. In the photoelectric converting device, a photo diode is connected to an input terminal of an amplifier to which a feedback resistor is connected, and the output current of this photo diode is converted into a voltage, and the converted voltage is obtained from the outside of the amplifier. When composing such photoelectric converting device by an integrated circuit, the feedback resistor is provided in the semiconductor integrated circuit device. When a resistor is formed in a region for a resistor formation use (hereinafter referred as to "resistor land") in the semiconductor substrate, an inverse bias is applied to the PN junction which is formed between the resistor region and the resistor land so that the PN junction may not conduct. Conventionally, to realize this inverse bias, the resistor land was connected to the power source line, that is, the power source line of the amplifier.
By applying an inverse bias to the PN junction between the resistor region and resistor land, a stray capacitor occurs in the PN junction portion. Therefore, when a power source voltage is applied to the resistor land, ripple caused by fluctuation of the power source voltage due to operating condition of other circuits or the like connected to the power source line may mix into the output of the photoelectric converting device through the stray capacitor.